En halua odottaa turhaan pysäkillä.

Yes. In Finnish, negation is made with a special negative verb, not with a separate word like English not.

For I do not, the form is en.

So:

• haluan = I want
• en halua = I do not want

The negative verb changes for person:

• en = I do not
• et = you do not
• ei = he/she/it does not
• emme = we do not
• ette = you all do not
• eivät = they do not

So en already tells you the subject is I.

Because Finnish often leaves out subject pronouns when they are already clear from the verb form.

Here, en already shows first person singular, so minä is not necessary.

You could say:

• Minä en halua odottaa turhaan pysäkillä.

But that sounds more emphatic, like I don’t want to wait there in vain.

In neutral Finnish, leaving out minä is very common.

Because after the negative verb en, the main verb appears in a special form called the connegative.

Compare:

• haluan = I want
• en halua = I do not want

So in negative sentences, you do not use the normal personal ending on the main verb. The person is already shown by en.

After haluta (to want), Finnish uses the first infinitive, which is the dictionary form of the verb.

So:

• haluan odottaa = I want to wait
• en halua odottaa = I do not want to wait

Finnish does not use a separate word like English to here. The infinitive form odottaa already does that job.

Finnish odottaa does not use a preposition like English for.

If you say what you are waiting for, it usually comes directly as an object:

• Odotan bussia. = I’m waiting for a bus.
• Odotan ystävääni. = I’m waiting for my friend.

In your sentence, the thing being waited for is simply not mentioned. So odottaa appears without an object.

Turhaan is an adverb. It modifies the verb odottaa and tells you how or with what result the waiting happens.

It means things like:

• in vain
• for nothing
• needlessly
• unnecessarily

So it does not describe a noun; it describes the action of waiting.

A good way to learn it is as a fixed expression:

• odottaa turhaan = wait in vain

Pysäkillä is the adessive case, with the ending -lla / -llä.

The adessive often means:

• on
• at

So:

• pysäkki = stop
• pysäkillä = at the stop

In this sentence, it tells you the location of the waiting.

Because pysäkki has front vowels (ä), the ending appears as -llä, not -lla.

This is due to consonant gradation, a very common Finnish sound pattern.

In many inflected forms, kk becomes k:

• pysäkki
• pysäkin
• pysäkillä

So the stem changes when you add endings.

This is something English speakers often have to get used to, because Finnish nouns often change their stem slightly in different cases.

Not usually. Pysäkki means a stop, typically a bus stop or tram stop.

It is different from a station such as:

• asema = station

So pysäkillä usually means at the stop, not at the station.

Yes. Finnish word order is more flexible than English word order.

This sentence has a very natural, neutral order:

• En halua odottaa turhaan pysäkillä.

But other orders are possible if you want to emphasize something:

• Pysäkillä en halua odottaa turhaan.
  Emphasizes at the stop.
• En halua turhaan odottaa pysäkillä.
  Brings turhaan a little more forward.

The original version is a normal, unmarked way to say it.

Yes, a few important ones:

• y in pysäkillä is not like English y. It is like German ü or French u.
• ä is a front vowel, somewhat like the vowel in English cat, but cleaner and more consistent.
• Double letters matter in Finnish:
  • odottaa has a long tt
  • pysäkillä has a long ll
• Stress is normally on the first syllable:
  • EN halua
  • ODottaa
  • PYsäkillä

Finnish pronunciation is very regular, so once you know the sound rules, the spelling helps a lot.